The market access rule requires broker-dealers to institute adequate risk controls for customers with access to the markets. Without sufficient controls on one account, a rogue trader was able to exceed his pre-set limit and order $525 million worth of Apple stock on October 25, 2012, an SEC investigation found.

An employee of Rochdale Securities, the trader had intentionally enlarged an actual customer order of Apple stock from 1,625 shares to 1,625,000 shares with the idea of profiting personally from the extra shares if the stock price increased or claim an order error if the stock price decreased, the SEC said.

Apple shares fell that day and the trader was unable to uphold the false claim of an error order, leaving Rochdale with a $5.3 million loss that ultimately caused its demise, the release said.